TabsController indicator line bug

[melcug]

I use following code to initialize TabBar:

extension AppTabBarController {
    fileprivate func prepareTabBar() {
        tabBarAlignment = .top
        tabBar.tabBarStyle = .auto
        tabBar.dividerColor = nil
        tabBar.lineHeight = 5.0
        tabBar.lineColor = Color.blue.lighten3
        tabBar.lineAlignment = .bottom
        tabBar.backgroundColor = Color.blue.darken2
    }
}

As you can see, there are some problems with indicator line shown on active tab:

• initially the line is moving from top (not from bottom) of latest active tab to next active tab;
• the line height is ok at start, but changing the active tab to other tab it changes also the height of the line.

Regards,
Gogu.

[daniel-jonathan]

Nice, I will investigate this today :) Thank you!

[daniel-jonathan]

Thank you for submitting this issue. It is now fixed. I will push an update now.

[melcug]

In latest version of Material (v2.9.1) the bug mentioned in first message (both issues) came back (fixed in v2.9.0).

Regards,
Gogu.

[egenvall]

This issue exists in v2.9.4 as well on the first swap between tabs

[daniel-jonathan]

I will double check.

[daniel-jonathan]

I cannot reproduce it. Are you sure you are using the latest? That said, if you can provide reproduction steps, that would be helpful. Thank you!

[egenvall]

Using Material (2.9.4)

class AppTabBarController: TabsController {

    override func viewDidLoad() {
        viewControllers = [someVc, someVc2]
        super.viewDidLoad()
    }


    open override func prepare() {
        super.prepare()
        tabBar.tabBarStyle = .auto
        tabBarAlignment = .top
        tabBar.dividerColor = nil
        tabBar.lineHeight = 5.0
        tabBar.lineColor = .red
        tabBar.lineAlignment = .bottom
        tabBar.backgroundColor = .white
    }
}

The only difference I guess is that AppTabBarController is one of the tabs in RamAnimatedTabBarController and then the Material TabsController has two viewcontrollers that is set in the viewDidLoad

[daniel-jonathan]

Hmmm... well I cannot reproduce this within Material, you would have to setup a sample project with another library and demonstrate how Material breaks. Then I would be happy to help out.

[egenvall]

It seems to be storyboard related (modified the sample)

class AppDelegate: UIResponder, UIApplicationDelegate {

var window: UIWindow?

func applicationDidFinishLaunching(_ application: UIApplication) {
    window = UIWindow(frame: Screen.bounds)
    window!.rootViewController = AppTabsController(viewControllers: [])
    window!.makeKeyAndVisible()
}

}

class AppTabsController: TabsController {

override func viewDidLoad() {
    viewControllers = [UIStoryboard(name: "Test", bundle: nil).instantiateViewController(withIdentifier: "blue"),UIStoryboard(name: "Test", bundle: nil).instantiateViewController(withIdentifier: "brown")]
    
    super.viewDidLoad()
}

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    navigationController?.navigationBar.isHidden = true
}

open override func prepare() {
    super.prepare()
    tabBar.tabBarStyle = .auto
    tabBarAlignment = .top
    tabBar.dividerColor = nil
    tabBar.lineHeight = 5.0
    tabBar.lineColor = .red
    tabBar.lineAlignment = .bottom
    tabBar.backgroundColor = .white
    tabBar.scrollView.showsVerticalScrollIndicator = false
    tabBar.scrollView.showsHorizontalScrollIndicator = false
    

    }
}

Created a storyboard "Test" with 3 ViewControllers

• AppTabsController: Custom class AppTabsController
• BlueViewController: Custom class BlueViewController
• BrownViewController: Custom class BrownViewController

i.e it's not related to the other library
This replicates the issue 100% success rate on the initial swap between the viewcontrollers

[daniel-jonathan]

I need a sample project that creates this issue. As well, you shouldn't need to set this:

tabBar.scrollView.showsVerticalScrollIndicator = false
tabBar.scrollView.showsHorizontalScrollIndicator = false

They should already be set.

[egenvall]

Demo Repo
(Didn't clean away the other files from the sample)
Yes you are correct regarding the scrollview indicators.

[James-Coleman]

@egenvall I know this is a really old issue and you may have already solved this, but I had this same issue and it was solved by setting up my tabBar appearance before calling super.viewDidLoad in my subclass of TabsController:

    override func viewDidLoad() {

        setupTabBarAppearance() // Setting up the tab bar appearance before super.viewDidLoad is removing the bug where the tab line would jump from the top to the bottom the first time a new tab is selected.
        
        super.viewDidLoad()
    }

I suspect this may be related to setting the tabBarAlignment to .top